Tafel Slope Research Articles

Plasma sprayed high-entropy alloy coatings with enhanced water splitting activity in alkaline environment

Developing highly efficient electrocatalysts for water splitting is an effective strategy to promote renewable and sustainable energy resources. Multimetal high-entropy alloys (HEAs) have generated considerable attention as promising catalysts because of their unique properties. Herein, the porous HEA coatings have been prepared via the plasma spraying method, which is expected to resolve the above issues. The catalysts can afford a promising catalytic performance through the distinct porous structure. This work results that the CoCrFeNiAlMo catalyst possesses a tiny overpotential (253mV at 50mAcm-2) with minimal Tafel slope (59.75mV dec-1). At the same time, the CoCrFeNiAlMo catalyst also exhibits a relatively small overpotential for hydrogen evolution reaction. As catalysts for overall water splitting, it delivers a cell voltage of 1.74V at 50mAcm-2 and a superior durable for 48h. This research provides an insight for using the multinary HEA coatings as electrocatalysts in energy applications.

Understanding the electrocatalytic role of magnesium doped bismuth copper titanate (BCTO) in oxygen evolution reaction

Designing high-efficiency electrocatalysts for water oxidation has become increasingly important in the catalysis field owing to its implications for renewable energy production and storage. The production of hydrogen (H2) from water is hampered by the very sluggish kinetics of the water-splitting process. Enhancement of effective oxygen evolution reaction (OER) electrocatalysts is also required to understand the primary barrier to OER. This article investigates the electrochemical activity of magnesium-doped bismuth copper titanate (Mg-BCTO) as an efficient catalyst for the OER in water electrolysis, a critical step in hydrogen production for sustainable energy. The synthesized materials, including various stoichiometries of Mg-doped BCTO, undergo thorough physical and electrochemical characterization using XRD, FT-IR, Raman, SEM, TEM, XPS, CV, EIS, and Tafel polarization analyses. Remarkably, Mg0.1 doped BCTO demonstrates superior performance, achieving a current density of 10 mA cm−2 at a very low overpotential (η10) of 265 mV and with a Tafel slope of 92 mV dec−1. This finding not only highlights the electrocatalytic efficiency of Mg doped BCTO but also positions it as a promising model for the development of highly active and stable water oxidizing catalysts, contributing to the advancement of clean energy technologies.

Hydrothermal synthesis of CeSe anchored on graphitic carbon nitride nanoclusters as an electrocatalyst for enhanced oxygen evolution reaction

The oxygen evolution reaction (OER) is a critical half-reaction in the process of water splitting, yet its practical application is hindered by slow kinetics and the high cost of conventional electrocatalysts. This study explores the potential of a novel CeSe/g-C3N4 nanocomposite as an efficient catalyst for OER in an alkaline environment. The CeSe/g-C3N4 nanocomposite exhibits exceptional electrocatalytic performance, demonstrated by a low overpotential of 196 mV at a current density of 10 mA cm−2 and a reduced onset potential of 1.29 V versus the reversible hydrogen electrode (RHE). Additionally, nanocomposite's Tafel slope of 58.14 mV/dec is significantly lower compared to pure CeSe (76.89 mV/dec) and multi-layered g-C3N4 (89.76 mV/dec), indicating superior kinetic behavior. Remarkably, the CeSe/g-C3N4 composite also demonstrates excellent electrochemical stability, maintaining its performance over a 40-hour period. These findings suggest that the CeSe/g-C3N4 nanocomposite not only enhances the electrocatalytic properties necessary for OER but also holds the potential to outperform traditional noble metal-based catalysts, paving the way for more cost-effective and efficient water-splitting technologies.

Surface-selenization formed NiFe MOF@NiSex heterogeneous arrays for enhanced oxygen evolution and methanol electrooxidation

Designing reasonable electrocatalysts for oxygen evolution reaction (OER) is a vital issue for water splitting to hydrogen. We report a surface-selenization of NiFe MOF-74 formed NiFe MOF@NiSex arrays through the simple solvothermal method. The NiFe MOF@NiSex heterostructures greatly enhance the charge transfer and cooperativity of active sites and result in strong adsorption capacity for OH– to strongly boost the OER and MOR process. The optimized electrode shows the highly efficient catalytic activity for OER with a low onset potential of 1.31 V vs. RHE and small Tafel slopes of 38.3 mV dec−1 in alkaline media. And it shows the extremely low overpotential of 229 and 329 mV at 100 and 500 mA cm−2. Moreover, its current density can reach more than 500 mA cm−2 at the potentials of 1.645 V vs. RHE at 0.8 M methanol/1 M KOH electrolyte, and it shows very good long-term stability at large current density. This heterogeneous arrays electrocatalysts may play a positive role in energy conversion and storage process.

Design and construction of robust nickel-based MOFs for promoting HER catalytic activity

The proposal of the dual-carbon target has attracted widespread attention to explore hydrogen evolution reaction (HER) electrocatalysts to promote the development of clean energy. Here, we propose a strategy to form hierarchically porous electrocatalytic hydrogen evolution catalysts (MOFs I−II) by calcining prefabricated Ni-metal–organic frameworks (MOFs 1 − 2) under N2 atmosphere. Among them, three-dimensional (3D) porous MOFs 1 − 2 have been synthesized by solvothermal method based on scissor-shaped tetracarboxylic acid, named {[Ni2(L)(1,3-bit)(H2O)3](C2H3N)}n (MOF 1) and [Ni4(tib)(L)2(H2O)3(μ2-O)]n (MOF 2). Single crystal diffraction analysis shows that MOF 1 is 3,4,7-connected 3-nodes 3D framework composed of two kinds 2D planes, while MOF 2 is 2,4,7-connected 3-nodes 3D supramolecular structure constructed from 1D chains and 2D planes. As expected, SEM and BET analysis show that calcination produced a unique hierarchical micro-mesoporous structure, while the specific surface area increases by 2.3–3.8 times. The optimized MOF II exposes more active sites, accelerates electrolyte ion diffusion, and has lower electron transfer resistance, allowing it to exhibit excellent electrocatalytic HER performance in an alkaline environment. Notably, MOF II has a Tafel slope of 81 mV·dec−1 (10 mA·cm−2) with a lower overpotential (225 mV). Compared with the pristine MOF 2, the performance of MOF II is significantly improved and it can operate stably for a long time. The possible electrocatalytic HER mechanism has been investigated by density functional theory (DFT). The results are expected to provide inspiration for the rational design and development of stable and efficient MOF-based HER electrocatalysts.

Orange peel derived activated carbon supported Ni–Co3O4 as an efficient electrocatalyst for oxygen evolution and reduction reaction in alkaline media

This study focuses on the development of a cost-effective electrocatalyst with excellent activity and stability for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), which is crucial for water electrolysis and fuel cell technologies. Waste orange peel is utilized as a carbon precursor to synthesize biomass-derived activated carbon (OPAC) with a unique three-dimensional sheet-like microstructure. Subsequently, a simple hydrothermal method is employed to modify the OPAC by introducing Ni-doped Co3O4, leading to the formation of a Ni–Co3O4/OPAC hybrid. We propose the Ni–Co3O4/OPAC hybrid as a highly efficient bifunctional electrocatalyst for both OER and ORR. Co3O4/OPAC and Co3O4 catalysts are also prepared for comparison. Remarkably, the Ni–Co3O4/OPAC hybrid exhibits significantly enhanced OER activity compared to Co3O4/OPAC and Co3O4 catalysts. It demonstrates a lower overpotential of 360 mV and a lower Tafel slope of 55.47 mV/dec, indicative of more efficient electrochemical performance. Moreover, in the ORR analysis, the Ni–Co3O4/OPAC hybrid displays a two-step pathway and achieves a higher ORR limiting current density compared to the Co3O4/OPAC and Co3O4 catalysts. These results highlight the synergistic effects of Ni and Co species, along with the unique properties of the OPAC support, which contribute to the enhanced activity, stability, and electron transfer characteristics of the Ni–Co3O4/OPAC hybrid. Furthermore, the improved electrical conductivity of the Ni–Co3O4/OPAC hybrid makes it a promising candidate for applications in metal-air batteries and other energy conversion devices. The utilization of waste orange peel as a carbon precursor and the facile synthesis method demonstrate the potential for cost-effective and sustainable electrocatalyst production. Overall, the Ni–Co3O4/OPAC hybrid represents a significant advancement in electrocatalyst design and holds promise for advancing the field of energy conversion and storage.

Effective Improvement of Thermodynamics and Kinetics of BiVO4 Photoanode via CuI for Photoelectrochemical Water Oxidation.

The preparation of durable and efficient photoanodes for photoelectrochemical water oxidation is of great importance in promoting the development of green hydrogen production and artificial photosynthesis. Here, n-type BiVO4 was combined with p-type CuI to construct a CuI/BiVO4 (CIB-1) p-n heterojunction photoanode. The composite photoanode effectively overcame the drawbacks of BiVO4, such as low separation and injection efficiency of photogenerated electron-hole pairs. As a result, the CIB-1 had the highest photocurrent density of 1.98 mA cm-2, which was 2.5 times higher than pure BiVO4 with 0.79 mA cm-2 at 1.23 V (vs RHE) under AM 1.5G light irradiation. The CIB-1 had a lower Tafel slope of 23.2 mV decade-1 compared to 47.9 mV decade-1 for BiVO4, so the water oxidation kinetics was remarkably advanced over CuI/BiVO4. Based on DFT calculations, the OER overpotential of 0.480 V for CuI/BiVO4 was significantly lower than that of 1.546 V for BiVO4 due to the lower free energy from OH- to oxygen over CuI/BiVO4 compared to BiVO4.

FeNi-Based Aerogels Containing FeNi3 Nanoclusters Embedded with a Crystalline–Amorphous Heterojunction as High-Efficiency Oxygen Evolution Catalysts

In green hydrogen production via water electrolysis, catalysts with multiscale nanostructures synthesized by compositing micro-heterojunctions and nanoporous structures exhibit excellent electrocatalytic oxygen evolution reaction (OER) performance. Moreover, they are the most promising non-noble metal catalysts. Herein, FeNi-based aerogels with a three-dimensional nanoporous structure and amorphous matrix embedded with FeNi3 nanoclusters were synthesized via wet chemical reduction coprecipitation. The FeNi3 nanoclusters and the FeNi-based amorphous matrix formed a crystalline–amorphous heterojunction. These aerogels exhibited excellent OER performance and electrocatalytic stability in alkaline electrolytes. In 1 mol/L of KOH electrolyte, the as-synthesized aerogel exhibited an overpotential of 262 mV at a current density of 20 mA cm−2 with a Tafel slope of only 46 mV dec−1. It also demonstrated excellent stability during a 12 h chronopotentiometry test.

Biomass Electrocatalysts: Exploiting Haemoglobin-derived Fe Sites Supported by Waste-derived, S and N-enriched Carbon for Efficient Oxygen Electro-reduction

Abstract Biomass resources offer a diverse array of low-cost feedstocks having interesting functional properties for the manufacture of electrocatalysts for the energy sector. In this study, haemoglobin (Hb), lignin, tannic acid and urea were used to make high surface area N, S-codoped carbon electrodes rich in highly dispersed heme-like (Fe-Nx) sites. By pyrolyzing precursor mixtures containing un-purified Hb, lignin, tannic acid and urea, in appropriate mass ratios, a high surface-area S, N-codoped carbon nanostructured electrocatalyst was obtained. The electrocatalyst had surface pyridinic and pyrrolic species together with highly dispersed N-coordinated Fe sites. The developed FeSN/C electrocatalyst exhibited an ORR onset potential of 0.98 V vs. RHE in 0.1 M KOH, a half-wave potential of 0.87 V and a low Tafel slope of 54 mV/dec. This work encourages the design of biomass-derived electrocatalysts for ORR, in particular showing that haemoglobin in bovine blood is suitable for use as an iron source when making Fe-N-C electrocatalysts.

Self‐supported thin‐film electrode consisting of transition metal borides for highly efficient hydrogen evolution

AbstractTransition metal borides (TMBs) are a new class of promising electrocatalysts for hydrogen generation by water splitting. However, the synthesis of robust all‐in‐one electrodes is challenging for practical applications. Herein, a facile solid‐state boronization strategy is reported to synthesize a series of self‐supported TMBs thin films (TMB‐TFs) with large area and high catalytic activity. Among them, MoB thin film (MoB‐TF) exhibits the highest activity toward electrocatalytic hydrogen evolution reaction (HER), displaying a low overpotential (η10 = 191 and 219 mV at 10 mA cm−2) and a small Tafel slope (60.25 and 61.91 mV dec−1) in 0.5 M H2SO4 and 1.0 M KOH, respectively. Moreover, it outperforms the commercial Pt/C at the high current density region, demonstrating potential applications in industrially electrochemical water splitting. Theoretical study reveals that both surfaces terminated by TM and B atoms can serve as the active sites and the H* binding strength of TMBs is correlated with the p band center of B atoms. This work provides a new pathway for the potential application of TMBs in large‐scale hydrogen production.

High‐Performance MCNTs@MoS2(1‐x)Se2x Nanocomposites in Catalytic Hydrogen Evolution

AbstractAdvances in electrocatalysis require the development of high specific surface area materials with high electron conductivity. In this study, a series of MCNTs@MoS2(1‐x)Se2x nanocomposites has been prepared for application in catalytic hydrogen evolution. A uniform growth of MoS2(1‐x)Se2x nanoflower spheres on MCNTs has been achieved, circumventing stacking and aggregation. The introduction of the conducting material accelerated the electron transport rate in the electrode reaction. Structural characterization has confirmed that S doping increased the specific surface area of the catalyst, exposing more edge defects. As a result, the MCNTs@MoS2(1‐x)Se2x nanocomposites exhibited enhanced catalytic activity. Electrochemical tests have established that MCNTs@MoS1.5Se0.5 possessed the lowest overpotential (146 mV) at a current density of 10 mA/cm2 with the smallest Tafel slope (45.1 mV/dec).

Roles and influencing mechanisms of guar gum and polyethylene glycol in copper electrodeposition

ABSTRACT In this paper, the effects of the organics guar gum and polyethylene glycol (PEG) additives on Cu electrodeposition cell voltage, energy consumption and surface morphology were evaluated. Furthermore, the influences of guar gum and PEG on the kinetics of Cu electrodeposition were investigated using electrochemical tests such as cyclic voltammetry (CV), linear sweep voltammetry (LSV) and Tafel linear fitting. The results indicated that adding 0.5 mg/L guar gum promoted the Cu electrodeposition. While indicating the lowest overpotential (10 and 100 mA cm−2 were −462 and −561 mV, respectively) and smaller Tafel slope of 50.37 mV dec−1. However, higher concentrations of guar gum and PEG increased cell voltage and energy consumption, with 900 mg/L PEG leading to a 61 kWh energy increase. Elevated organic levels in the electrolyte raised overpotential, inhibiting Cu deposition and causing surface roughness on Cu sheets.

Versatile platform of 3D/2D/1D:ZnFe2O4/NiAl-LDH/MWCNTs nanocomposite for photocatalytic purification of dinoseb and electrocatalytic O2 evolution reaction.

Integrating photocatalysis with electrocatalysis may represent a synergistic approach to address environmental and energy challenges. In this context, we explored synthesizing a series of nanocomposite materials using a solid-state approach involving simple grinding and subsequent thermal treatment for the photocatalytic purification of dinoseb and electrocatalytic oxygen evolution (OER). Interestingly, among the series of synthesized materials, 40 weight percentage of 3D/2D/1D:ZnFe2O4/NiAl-LDH/MWCNTs ternary nanocomposite (40-NZM) showed highly improved dinoseb detoxification and OER efficiencies compared to those of pure materials. Importantly, approximately 98% detoxification of dinoseb was observed within 75 min of irradiation time under a visible light source. Remarkably, the 40-NZM nanocomposite exhibited the highest rate constant value (k = 4.1×10-2 min-1) with a favorable R2 (0.98) parameter. Furthermore, 40-NZM showed promising electrocatalytic OER performance, requiring only 217 mV of overpotential to achieve 10 mAcm-2 of current density with a smaller Tafel slope of 66.6 mVdec-1. Additionally, long-term stability was tested by recording 2000 cyclic voltammetry (CV) cycles. The results revealed that 40-NZM could maintain its catalytic activity for a longer duration as it required only 227 mV to attain 10 mAcm-2 even after 2000 CV cycles. Consequently, these outstanding characteristics of 40-NZM nanocomposite underscore the significant potential for catalytic water purification and sustainable energy conversion.

On the Quest for Oxygen Evolution Reaction Catalysts Based on Layered Double Hydroxides: An Electrochemical and Chemometric Combined Approach

The oxygen evolution reaction (OER) is a crucial process in various energy conversion and storage technologies, such as water electrolysis. Developing efficient and cost‐effective electrocatalysts is essential to achieve the commercialization of devices for the transition toward sustainable energy solutions. Herein, ternary layer double hydroxides (LDHs) are synthesized and characterized as electrocatalysts for OER using a potentiodynamic electrochemical deposition method on Grafoil. A chemometric approach based on experimental design is employed to rationalize the effort in the investigation of the LDHs which are based on Ni, Co, and Fe. The deposited films are characterized using cyclic voltammetry and X‐ray diffraction to determine peak currents and potentials, and crystal size. Furthermore, the electrocatalyst performances are assessed by linear sweep voltammetry in 1M KOH from which the Tafel slope and onset potential are calculated. The obtained data are used to derive models describing the material properties and electrocatalyst performance as a function of the electrolyte composition used during the LDHs electrodeposition. This study provides valuable insights into the relationship between the electrocatalyst composition and its OER activity, enabling the design of more efficient and sustainable electrochemical systems for energy applications.

Hydrogen Evolution Reaction of Electrodeposited Ni-W Films in Acidic Medium and Performance Optimization Using Machine Learning.

Ni-W alloy films were electrodeposited from a gluconate aqueous bath at pH=5.0, at varying current densities and temperatures. While there is little to no difference in composition, i. e., all films possess ~12 at.% W, their activity at hydrogen evolution reaction (HER) in acidic medium is greatly influenced by differences in surface morphology. The kinetics of HER in 0.5 M H2SO4 indicates that the best performing film was obtained at a current density of -4.8 mA/cm2 and 50 °C. The Tafel slopes (b) and the overpotentials at a geometric current density of -10 mA/cm2 (η10) obtained for 200 cycles of linear sweep voltammetry (LSV) from a set of films deposited using different parameters were fed into a machine learning algorithm to predict optimum deposition conditions to minimize b, η10, and the degradation of samples over time. The optimum deposition conditions predicted by the machine learning model led to the electrodeposition of Ni-W films with superior performance, exhibiting b of 33-45 mV/dec and an η10 of 0.09-0.10 V after 200 LSVs.

Engineering MXene Surface via Oxygen Functionalization and Au Nanoparticle Deposition for Enhanced Electrocatalytic Hydrogen Evolution Reaction.

MXene, a family of 2D transition metal carbides and nitrides, presents promising applications in electrocatalysis. Maximizing its large surface area is key to developing efficient non-noble-metal catalysts for the hydrogen evolution reaction (HER). In this study, oxygen-functionalized Ti3C2Tx MXene (Ti3C2Ox) is synthesized and deposited gold nanoparticles (Au NPs) onto it, forming a novel composite material, Au-Ti3C2Ox. By selectively removing other functional groups, mainly -O functional groups are retained on the surface, directing electron transfer from Au NPs to MXene due to electronic metal-support interaction (EMSI), thereby improving the catalytic activity of the MXene surface. Additionally, the interaction between Au NPs and -O functional groups further enhanced the overall catalytic activity, achieving an overpotential of 62 mV and a Tafel slope of 40.1 mV dec-1 at a current density of -10 mA cm-2 in 0.5 m H2SO4 solution. Density functional theory calculations and scanning electrochemical microscopy with ≤150 nm resolution confirmed the enhanced catalytic efficiency due to the specific interaction between Au NPs and Ti3C2Ox. This work provides a surface modification strategy to fully utilize the MXene surface and enhance the overall catalytic activity of MXene-based catalysts.

ZIF-67 derived N doped carbon embedded CoxP for superior hydrogen evolution

Abstract Developing a sustainable non-noble hybrid electrocatalyst for effective electrocatalysis is the most crucial task; particularly in sustainable hydrogen energy production in the realm of energy conversion. In this work, effective thermal pyrolysis process followed by phosphorization strategy was employed to prepare and fabricate ZIF-67 (Zeolitic imidazole) assisted Co2P/N doped carbon electrocatalyst for hydrogen evolution reaction (HER). The optimized Co2P/N–C electrocatalyst exhibited hollow porous nanostructures as confirmed from the scanning electron microscopy. The achieved porous nanostructure improved the efficiency of the charge and mass transportation which is confirmed by the BET analysis, has high surface area value of 94.731 m2/g. In addition, a transition metal atom can regulate reactants adsorption and desorption capacity by modulating Co and P electronic configuration. The electrochemical studies of fabricated ZIF-67 derived Co2P/N–C electrode were analyzed using 1.0 M alkaline potassium hydroxide (KOH) medium in 3 electrode system process. Whilst, optimizing the pyrolysis temperature during the phosphorization will remarkably enhance the favourable characteristics of the hydrogen generation. Notably, the optimized ZIF-67 derived Co2P/NC at 350 °C electrode exhibited low overpotential (135 mV) at minimum 10 mA/cm2 and low 120.3 mV/dec Tafel slope. Besides, electrode stability at 10 mA/cm2 current density was verified by chronoamperometry test. Hence, this study furnishes the potential technique for the development of advanced hybrid MOF electrocatalyst as a successful alternative on large scale.

CuS-NiTe2 embedded phosphorus-doped graphene oxide catalyst for evaluating hydrogen evolution reaction.

The hydrogen evolution reaction (HER), a crucial half-reaction in the water-splitting process, is hindered by slow kinetics, necessitating efficient electrocatalysts to lower overpotential and enhance energy conversion efficiency. Transition-metal electrode materials, renowned for their robustness and effectiveness, have risen to prominence as primary contenders in the field of energy conversion and storage research. In this investigation, we delve into the capabilities of transition metals when employed as catalysts for the HER. Furthermore, we turn our attention to carbon nanomaterials like graphene, which have exhibited tremendous potential as top-performing electrocatalysts. Nevertheless, advancements are indispensable to expand their utility and versatility. One such enhancement involves the integration of phosphorus-doped graphene. Our research focuses on the synthesis of CuS-NiTe2/PrGO, a nanocomposite with a crystalline structure, through a straightforward method. This nanocomposite exhibits enhanced catalytic activity for the HER, boasting a Tafel slope of 57 mV dec-1 in an acidic environment. Consequently, our findings present a straightforward and efficient approach to developing high-performance electrocatalysts for HER.

Fluorine-Induced Lattice Oxygen Participation in 2D Layered Double Hydroxide/MXene Hybrids for Efficient Oxygen Evolution.

In oxygen evolution reaction (OER), the participation of lattice oxygen can break the limitation of adsorption evolution mechanism, but the activation of lattice oxygen remains a critical challenge. Herein, a surface fluorinated highly active 2D/2D FeNi layered double hydroxide/MXene (F-LDH/MX) is demonstrated, boosting OER with the enhanced lattice-oxygen-mediated path. The introduction of fluorine promotes the self-evolution of catalyst in an alkaline environment, even without an external current. It further accelerates the formation of active metal oxyhydroxides with abundant oxygen vacancies under the operating potential. The introduced oxygen vacancy activates the lattice oxygen, increasing the proportion of lattice oxygen mechanism in OER. Owing to the synergistic effects of the 2D/2D hierarchical structure and the modulated active surface, F-LDH/MX possesses excellent electrochemical performances, including a low overpotential of 251 mV at 10 mA cm-2, a low Tafel slope of 40.28 mV dec-1, and robust stability. The water electrolyzer system with F-LDH/MX as the anode offers the benchmark current density at a low cell voltage of 1.53 V, while the Zn-air battery with F-LDH/MX as the air electrode exhibits a higher power density of 75.43 mW cm-2. This study presents a promising strategy to design highly active electrocatalysts for energy conversion and storage.

Structural Regulation of a Multi-Component Co2P2O7-MoN/NC Electrocatalyst for Efficient Oxygen Evolution Reaction.

Realizing efficient and durable non-precious metal-based electrocatalysts for oxygen evolution reaction (OER) still remains a great challenge. Here, a multi-component composite of Co2P2O7-MoN/NC containing pyrophosphate, nitride, and nitrogen-doped carbon is successfully prepared via a facile two-step synthesis method. Combining the structural regulation between the active metal- and non-metal-based species, Co2P2O7-MoN/NC demonstrates superior activity and durability for OER, requiring an overpotential of 278 mV at a current density of 10 mA cm-2, a Tafel slope of 83.3 mV dec-1, and long-term stability over 100 h in an alkaline solution. Post-characterizations reveal that synergistic effect among stable Co2P2O7, partially dissolved MoN, N-doped carbon, and new-formed CoOOH nanosheets enable structural reconstruction, fast charge transfer, and formation of oxygen-containing intermediates, promoting the OER performance significantly. This work provides a promising pathway to tune multi-components to fabricate efficient transition-metal-based electrocatalysts in energy conversion applications.